Merco MERCO Savory MHC-22-TDL, Parts And Service Manual

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5
TROUBLESHOOTING GUIDE (CONT’D)
Display reads
unusual characters
Make sure wires are connected properly
(grounded).
If wires are grounded properly, new control board
is needed.
On/Off switch doesn’t
light (but unit works
properly)
Power Switch Check wiring to switch.
HEAT SHELF – REPLACEMENT
1. Disconnect power.
2. Take out screws holding “L Brackets” in cavity.
3. Disconnect thermocouple and all power connections to board. Mark all wires for reassembly.
4. Take out power board.
5. Take out shelf mounting screws from both sides.
6. Remove shelves and feed wiring out of unit.
7. Reassemble in reverse order.
USER INTERFACE (U.I.) BOARD – REPLACEMENT
1. Remove four (4) screws.
2. Disconnect thermocouples.
3. Disconnect ribbon cable.
4. Remove board.
5. Reassemble in reverse order.
WARNING: Be careful to avoid tearing the aluminum foil while working with wire
connections.
!
!
When replacing U.I. board, be
sure ribbon cable is connected
so that blue wire is facing
towards interior of unit.